Factors associated with invasive lung aspergillosis and the significance of positive Aspergillus culture after liver transplantation.

From January 1981 to December 1990, 2180 patients underwent orthotopic liver transplantation at the University of Pittsburgh. Thirty-two patients (1.5%) were identified with invasive aspergillosis (29 lung, 2 intraabdominal, 1 meningitis). Of 29 patients with invasive lung disease, only 23 (79%) had positive culture (Aspergillus fumigatus, 20; Aspergillus flavus, 3). Forty-eight variables were analyzed and compared in 23 patients with invasive disease with positive cultures and 9 patients with colonization only. The variables associated with pulmonary invasive disease, by univariate analysis, were surgical time (P = .03), presence of laparotomies (P = .02), higher creatinine level at time of Aspergillus isolation (P = .01), and use of OKT3 (P = .02). However, in a multivariate analysis, only the last two (creatinine, OKT3) were associated with invasive lung aspergillosis. Of 4 patients with positive abdominal wound culture, 2 had local invasive aspergillosis. Therefore, positive cultures of Aspergillus organisms from respiratory secretions and wound drainage may represent invasive disease and should not be ignored.     

Risk factors for Candida infections in a neonatal intensive care unit in Costa Rica.

OBJECTIVE: To identify potential risk factors associated with Candida infections and compare these risk factors between patients who both died and survived. STUDY DESIGN: A group of patients with positive Candida spp. blood cultures admitted to a neonatal intensive care unit (NICU) in Costa Rica between January 1994 and December 1998. Cases were identified through a computerized search of the microbiology laboratory's database on blood cultures. RESULTS: One hundred and ten newborns were identified. Sixty-six patients (60%) were male; 46 (62%) were preterm infants. Thirty-seven (34%) patients died. Twenty (54%) of them died within three days of the candidemia diagnosis and 17 had disseminated Candida infection on autopsy. Candida albicans and Candida tropicalis were isolated in 90% and 10% of blood cultures, respectively. Mean +/- SD (range) number of days from admission to NICU to the initial positive blood culture were 13.5 +/- 8.5 (1-30) days. Most patients had at least two positive blood cultures (range 1-8). Median (range) days for the sterilization of blood culture were four (1-25) days. Significant differences in survival were identified in patients with axillary-inguinal lesions, apnea and seizures. CONCLUSIONS: Invasive fungal infections are frequent in NICU. Future case-control prospective studies should be carried out to confirm the findings from this report.     

Value of surveillance blood culture for early diagnosis of occult bacteremia in patients on corticosteroid therapy following allogeneic hematopoietic stem cell transplantation

Bloodstream infection (BSI) is a significant complication following allogeneic hematopoietic stem cell transplantation (allo-SCT). Corticosteroids mask inflammatory responses, delaying the initiation of antibiotics. We reviewed medical records of 69 allo-SCT patients who had been on >0.5 mg/kg prednisolone to investigate the efficacy of weekly surveillance blood cultures. A total of 36 patients (52%) had positive cultures, 25 definitive BSI and 11 probable BSI. Pathogens in definitive BSI were Staphylococcus epidermidis (n=7), S. aureus (n=4), Entrococcus faecalis (n=3), Pseudomonas aeruginosa (n=5), Acenitobacter lwoffii (n=4), and others (n=10). The median interval from the initiation of corticosteroids to the first positive cultures was 24 days (range, 1-70). At the first positive cultures, 15 patients with definitive BSI were afebrile. Four of them remained afebrile throughout the period of positive surveillance cultures. Patients with afebrile BSI tended to be older (P=0.063), and had in-dwelling central venous catheters less frequently than febrile patients (P<0.0001). Bloodstream pathogens were directly responsible for death in two patients with afebrile BSI. This study demonstrates that cortisosteroid frequently masks inflammatory reactions in allo-SCT recipients given conrticosteroids, and that surveillance blood culture is only diagnostic clue for 'occult' BSI.     

Hematogenous candida endophthalmitis in patients receiving parenteral hyperalimentation fluids

To determine the incidence of hematogenous candida endophthalmitis in seriously ill patients given parenteral hyperalimentation fluids, 131 hyperalimented postoperative patients were prospectively evaluated. All patients were screened weekly for the development of chorioretinal lesions, blood cultures positive for Candida albicans, and signs and symptoms of candida infection. Thirteen (9.9%) of 131 patients developed chorioretinal lesions compatible with hematogenous candida endophthalmitis. Seven of the 13 patients with eye lesions had blood cultures positive for yeast, whereas only two of 118 without eye lesions had blood cultures positive for yeast (P less than 0.0005). Thus, the occurrence of eye lesions consistent with hematogenous candida endophthalmitis correlated with positive blood cultures for yeast and strongly suggested invasive candidiasis.     

Incidence of bacteremia in transesophageal echocardiography: a prospective study of 140 consecutive patients

The incidence of bacteremia related to transesophageal echocardiography was studied in 140 consecutive patients (71 women and 69 men with a mean age of 53.7 +/- 15 years). Thirty-four patients had one or more prosthetic heart valves. Blood cultures were obtained from each patient through separate venipuncture sites immediately before and after transesophageal echocardiography. An additional late blood culture was obtained in 114 patients 1 h later. The skin was cleaned with povidone-iodine and venipunctures were performed with separate butterfly needles with use of sterile gloves and drapes. Blood samples were drawn into separate syringes, transferred to aerobic and anaerobic culture bottles and processed with use of a semiautomated system. The overall incidence of blood cultures positive for bacteremia was 2% (8 of 394 bottles) and all positive cultures grew in a single blood culture bottle. Positive cultures occurred in 4 (1.4%) of 280 bottles before the procedure, in 2 (0.7%) of 280 bottles immediately after the procedure and in 2 (0.9%) of 228 late (1-h) blood culture bottles. Bacterial isolates were coagulase-negative staphylococci (n = 5), Propionibacterium (n = 2) and Moraxella (n = 1). All were considered contaminants. Mean endoscopic time in these patients was not significantly different from that in the other patients. Follow-up of patients with a blood culture positive for bacteremia revealed no clinical evidence of systemic infection. It is concluded that 1) the incidence of bacteremia related to transesophageal echocardiography is very low, and 2) the incidence of blood cultures positive for bacteremia after transesophageal echocardiography is indistinguishable from the anticipated contamination rate.     

Detection of germline variants using expanded multigene panels in patients with localized pancreatic cancer

BackgroundCurrent guidelines recommend genetic testing for all patients with pancreatic cancer (PC).MethodsPatients with localized PC who received neoadjuvant therapy between 2009 and 2018 were identified. Genetic consultation (including personal and family history of cancer), genetic testing, and variant data were abstracted.ResultsOf 510 patients identified, 163 (32%) underwent genetic counseling and genetic testing was performed in 127 (25%). Patients who underwent genetic testing were younger (median age: 63 vs. 67, p = 0.01). Multi-gene testing was performed in 114 (90%) of 127 patients, targeted gene testing was performed in 8 (6%), and not specified in 5 (4%). Of 127 patients who underwent genetic testing, 20 (16%) had pathogenic (P)/likely pathogenic (LP) variants, observed in ATM (n = 7/105,7%), CHEK2 (n = 3/98, 3%), BRCA1 (n = 2/117, 2%), BRCA2 (n = 2/122, 2%), PALB2 (n = 1/115, 1%), MUTYH (n = 1/98, 1%), CDKN2A (n = 1/94, 1%), STK11 (n = 1/97, 1%), NBN (n = 1/98, 1%), and MSH6 (n = 1/97, 1%). Of 20 patients with either a P/LP variant, nine (45%) had a prior cancer, three (15%) had a first-degree relative with PC, and six (30%) had an any-degree relative with PC.ConclusionPathogenic/likely pathogenic variants were identified in 16% of patients who underwent genetic testing, 60% of which occurred in the homologous recombination pathway.     

Infectious endocarditis with negative blood cultures

Blood culture is a key investigation for the diagnosis of infectious endocarditis (IE). When negative, there are diagnostic and therapeutic problems. The aim of this study was to determine the frequency, the clinical features and the aetiological factors of IE with negative blood cultures compared with IE with positive blood cultures compared with IE with positive blood cultures. The authors undertook a retrospective review of 98 cases of patients admitted for IE from 1991 to 2000 to the Department of Infectious Diseases and Cardiology of Sousse (Tunisia). Of the 98 patients, 48 (48.9%), 29 men and 19 women with an average age of 34.3 years, had negative blood cultures. An infectious agent was identified in 7 cases (14.5%) by serology, valve culture or cerebrospinal fluid including Brucella (2), Coxiella (1) and Candida (1). Therefore, in 41 cases (42%), the cause of IE was not determined. Transthoracic echocardiography was of diagnostic value in 96% of cases and transoesophageal echocardiography showed disease not observed on transthoracic echocardiography in 5 cases. The main complication was cardiac failure (27 cases). The mortality was 14.5%. Comparison of the two groups showed that negative blood cultures were associated with a higher incidence of previous antibiotic therapy, extracardiac signs of IE and cardiac failure. Early surgical indications and mortality were the same in both groups. This report confirmed the high frequency of IE with negative blood cultures. Previous antibiotic therapy seems to be an important aetiological factor but cannot explain this high frequency. Methodological problems of blood cultures and the absence of systematic investigation for rare infectious agents are other possible factors.     

Invasive aspergillosis in acute leukemia: correlation with nose cultures and antibiotic use.

Aspergillosis in cancer patients is a problem. Because not all patients can undergo invasive procedures, we sought other methods for diagnosis. We reviewed the data from all patients with acute nonlymphocytic leukemia treated at our center during a 3-year period. Of 125 patients, 18 had invasive aspergillosis (cases). Eleven patients had nose cultures growing Aspergillus flavus or A. fumigatus; 10 of these 11 had aspergillosis, whereas only eight of 114 without such nose cultures had invasive disease (P less than 0.000001). Thus, A. flavus on nose culture appears "predictive" for aspergillosis. Absence of such a culture does not preclude infection. Of 125 patients, 61 had sterile nose culture(s) and 14 of the 18 cases had such a sterile nose culture. Only four of the 64 patients without sterile nose cultures developed aspergillosis (P less than 0.008), suggesting a relation between sterile nose culture and aspergillosis. Carbenicillin was used for a longer period among cases and patients with predictive nose cultures than among patients without aspergillosis. These data may help identify patients at risk of aspergillosis and help determine antifungal therapy when invasive procedures are contraindicated.     

Fungemia in HIV-infected patients: a 12-year study in a tertiary care hospital

Opportunistic infections caused by fungi are common in human immunodeficiency virus (HIV)-infected patients. We focused on severe infections as indicated by detectable fungemia. Medical charts available for patients having positive blood cultures with fungi at the University of Geneva Hospital were retrospectively (1989 to 2000) reviewed. Of 328 patients with fungemia during the study period, 315 (96%) medical charts were accessible. Of these 315 patients, 37 (12.2%) were HIV-positive, and 13 (35.1%) died within 6 months from their episode of fungemia. This was a lower mortality rate than for the HIV seronegative patients (45.8%). The median and average age of the 34 HIV-positive patients was 37.2 years, and 24 (64.9%) were males. Cryptococcus neoformans (n = 14) and Candida albicans (n = 12) were the most frequently identified species, followed by Candida glabrata (n = 3), of which 3 were mixed C. albicans + C. glabrata, Histoplasma capsulatum (n = 2), and Penicillium marneffei (n = 2). The frequency decreased significantly (p < 0.007) from the time period 1993 to 1996 (n = 21) to the period 1997 to 2000 (n = 6). Fungemias in HIV-infected patients have declined significantly since 1996. This coincides with the introduction of highly active antiretroviral therapy (HAART).     

Reduced acquisition and overgrowth of vancomycin-resistant enterococci and Candida species in patients treated with fidaxomicin versus vancomycin for Clostridium difficile infection

Fidaxomicin causes less disruption of anaerobic microbiota during treatment of Clostridium difficile infection (CDI) than vancomycin and has activity against many vancomycin-resistant enterococci (VRE). In conjunction with a multicenter randomized trial of fidaxomicin versus vancomycin for CDI treatment, we tested the hypothesis that fidaxomicin promotes VRE and Candida species colonization less than vancomycin. Stool was cultured for VRE and Candida species before and after therapy. For patients with negative pretreatment cultures, the incidence of VRE and Candida species acquisition was compared. For those with preexisting VRE, the change in concentration during treatment was compared. The susceptibility of VRE isolates to fidaxomicin was assessed. Of 301 patients, 247 (82%) had negative VRE cultures and 252 (84%) had negative Candida species cultures before treatment. In comparison with vancomycin-treated patients, fidaxomicin-treated patients had reduced acquisition of VRE (7% vs 31%, respectively; P < .001) and Candida species (19% vs 29%, respectively; P = .03). For patients with preexisting VRE, the mean concentration decreased significantly in the fidaxomicin group (5.9 vs 3.8 log(10) VRE/g stool; P = .01) but not the vancomycin group (5.3 vs 4.2 log(10) VRE/g stool; P = .20). Most VRE isolates recovered after fidaxomicin treatment had elevated fidaxomicin minimum inhibitory concentrations (MICs; MIC(90), 256 μg/mL), and subpopulations of VRE with elevated fidaxomicin MICs were common before therapy. Fidaxomicin was less likely than vancomycin to promote acquisition of VRE and Candida species during CDI treatment. However, selection of preexisting subpopulations of VRE with elevated fidaxomicin MICs was common during fidaxomicin therapy.     

Cimetidine therapy and duodenal candidiasis: role in healing process.

Patients with Candida colonization and invasion were studied in 20 duodenal ulcer (DU) patients, 10 non-ulcer dyspepsia (NUD) cases and 10 controls with non-gastroenterological disorders. Of 20 DU patients, Candida albicans was cultured from duodenal aspirates of 6 (30%) DU patients and pseudohyphae, indicating invasive form, were present in two (10%) prior to treatment. NUD patients and controls had positive Candida culture in 3 (30%) and 1 (10%) cases respectively; pseudohyphae were found in none. Six DU patients (30%) failed to heal with 4 weeks of cimetidine therapy; all six showed invasion of duodenal ulcer mucosa with Candida on histology. The pseudohyphae form of Candida was always found to be associated with non-healing of DU. Candidal invasion is associated with failure to respond to, H2-receptor antagonist therapy.     

Etiology of acute, non-malaria, febrile illnesses in Jayapura, northeastern Papua, Indonesia

We conducted a prospective, inpatient fever study in malaria-endemic Papua, Indonesia to determine non-malaria fever etiologies. Investigations included malaria blood films, blood culture, paired serologic samples analysis for dengue, Japanese encephalitis, leptospirosis, scrub typhus, murine typhus, and spotted fever group rickettsia. During 1997-2000, 226 patients (127 males and 99 females) 1-80 years of age (median age = 25 years) were enrolled. Positive blood cultures (n = 34, 15%) were obtained for Salmonella Typhi (n = 13), Escherichia coli (n = 8), Streptococcus pneumoniae (n = 6), Staphylococcus aureus (n = 5), Streptococcus pyogenes (n = 1), and Klebsiella pneumoniae (n = 1). Twenty (8.8%) patients were positive for leptospirosis by polymerase chain reaction. Eighty (35.4%) of 226 patients had ≥ 1 positive serology, diagnostic for 15 rickettsial and 9 dengue cases. Acid-fast bacilli-positive sputum was obtained from three patients. Most common confirmed (81 of 226, 35.8%)/suspected diagnoses were typhoid fever (n = 41), pneumonia (n = 29), leptospirosis (n = 28), urinary tract infections (n = 20), rickettsioses (n = 19), dengue (n = 17), and meningitis/encephalitis (n = 15). There were 17 deaths, 7 (46.7%) were caused by meningitis/encephalitis. Multiple positive serologic results and few confirmed diagnoses indicate the need for improved diagnostics.     

A pilot study of the management of uncomplicated candidemia with a standardized protocol of amphotericin B.

We evaluated an amphotericin treatment strategy on the basis of duration of candidemia and clinical findings. Patients without neutropenia who had uncomplicated candidemia received 200 mg of amphotericin B over 5-7 days if they had had 1 day of positive cultures (PC group). The clinical cure rate was 93% (95% confidence interval [CI], 77%-99%; n=29 episodes) in the SC group, with no relapses (median follow-up, 272 days). The clinical cure rate was 83% (95% CI, 64%-94%; n=29 episodes) in the PC group, with 1 relapse (4.2%). The results of this pilot study suggest that patients with candidemia may be stratified into risk groups on the basis of the duration of positive blood cultures and other clinical findings. Decisions about the duration of therapy can be made 4-7 days after initiation of treatment. Carefully selected patients with transient uncomplicated candidemia may be safely treated with a short course of amphotericin B. Further prospective validation of this concept should be undertaken particularly to evaluate the impact on low-frequency late complications (e.g., endophthalmitis).     

The predictors of outcome in immunocompetent patients with hematogenous candidiasis.

OBJECTIVE: Clinical parameters that predict outcome in non-immunosuppressed candidemic patients are not fully understood. METHODS: Eighty-one consecutive episodes of candidemia were retrospectively evaluated in 75 patients during 1998-2000. RESULTS: Infection due to Candida albicans was common (n = 30; 37%) followed by Candida glabrata (n = 25; 31%), Candida parapsilosis (n = 14; 17%), Candida tropicalis (n = 6; 7%), Candida krusei (n = 5; 6%), and Candida lusitaniae (n = 1; 1%). Among 70 evaluable patients, 31 (44%) had fungemia-associated mortality; advanced age (P < 0.004), underlying malignancy (P < 0.025), coronary artery disease (P < 0.01), and concurrent non-Candida species fungal infection (P < 0.047) were significant prognosticators of compromised short-term survival by multivariate analysis. Mortality was higher in patients with Candida glabrata (60%) and C. tropicalis (75%) infection compared to 44% deaths in individuals with C. albicans infection (P > 0.1). 11/25 (44%) of non-immunocompromised individuals died and 20/45 (44%) immunosuppressed patients succumbed to fungemia: persistent vs. non-persistent (< 3 days) Candida bloodstream invasion, neutropenia, diabetes mellitus, renal insufficiency, prior antimicrobial therapy, cirrhosis of liver, abdomino-pelvis surgery, and critical-care-unit vs. non critical-care-unit admission did not significantly impact outcome in either group. All 11 infants, including nine with prematurity, survived Candida species bloodstream infection (P < 0.025). CONCLUSIONS: Short-term mortality in candidemic non-immunocompromised patients was comparable to fungemia-associated deaths in immunosuppressed patients. Ischemic heart disease has appeared as a new predictor of unfavorable outcome in patients with hematogenous candidiasis.     

Candidemia in a tertiary care hospital: epidemiology, risk factors, and predictors of mortality.

Demographic information, risk factors, therapy, and outcome for all patients who had candidemia at Barnes Hospital, St. Louis, between 1 September 1988 and 1 September 1989 were retrospectively reviewed. One hundred six candidemic patients were identified, representing 0.5% of all medical and surgical discharges and 0.33% of total patient discharges. These percentages represent a 20-fold increase in the incidence of candidemia at our hospital in comparison with that during 1976-1979. Candida albicans was the most frequently isolated species (63%), followed by Candida tropicalis (17%), Candida glabrata (13%), Candida parapsilosis (6.5%), and Candida krusei (0.9%). Overall mortality was 57%, and 14 (23%) of 60 deaths occurred within 48 hours of the detection of candidemia. Mortality was associated with higher APACHE II scores (25 for nonsurvivors vs. 16 for survivors; P = .0001), the presence of a rapidly fatal underlying illness (P = .0009), and sustained positivity of blood cultures (P = .02). In cases of sustained candidemia, the isolation of non-albicans Candida species also correlated with increased mortality (8 of 8 vs. 10 of 21; P = .005). Thirty candidemic patients (28%) did not receive any antifungal therapy, and 19 (63%) of these untreated patients died. Eleven untreated patients (37%) survived without sequelae. There has been a marked increase in the incidence of candidemia in our institution that is associated with a high overall mortality. Candidemia lasting less than 24 hours was associated with a lower mortality than was that of longer duration. Severity of illness and duration of candidemia should be used as stratifying factors in prospective studies to determine optimum therapy.     

Candida antigen latex test for detection of invasive candidiasis in immunocompromised patients

Candida antigen latex agglutination testing was performed twice weekly during 217 admissions of 200 patients undergoing intensive chemotherapy alone or supported by autologous or allogeneic bone marrow transplantation. Eleven patients developed invasive candidiasis, three of whom survived; 6 (54.5%) of the 11 had positive Candida antigens. In 206 admissions, invasive candidiasis could not be documented. Of the 60 patients who died, 41 underwent autopsy examination, and 29 (71%) had positive Candida antigens. The latex test was also positive in 30 (20.5%) of the survivors and 10 (53%) of the unautopsied patients. Serum creatinine levels were greater than 2 mg/dL in 61% and 13% of patients with positive and negative Candida antigens, respectively (P less than .0001). For patients in whom the presence or absence of invasive candidiasis could be unequivocally demonstrated, the sensitivity, specificity, and positive and negative predictive values of the latex test at a titer of 1:4 were 54.5%, 29%, 17%, and 70.5%, respectively, suggesting that the latex test should not be used to diagnose invasive candidiasis in immunocompromised patients.     

Bone marrow cultures for the diagnosis of mycobacterial and fungal infections in patients infected with the human immunodeficiency virus.

SETTING: University medical center. OBJECTIVE: To determine the value of bone marrow cultures for mycobacteria and fungi in patients infected with the human immunodeficiency virus (HIV). DESIGN: Retrospective review of charts and laboratory records. RESULTS: From 1992-1996, 1225 bone marrow specimens were submitted for mycobacterial and fungal cultures. The number of specimens submitted,declined sharply from 435 in 1992 to 94 in 1996 (P = 0.002 for trend). The yield remained stable. Thirty-one of 1225 specimens grew mycobacteria or fungi; 26 isolates were from 24 HIV-infected patients. These 24 patients were infected with Mycobacterium avium complex (19), M. tuberculosis (one), M. chelonae (one), Histoplasma capsulatum (two), and Cryptococcus neoformans (one). All 24 HIV-infected patients had a culture submitted from at least one other site within 4 weeks of the positive bone marrow culture. The identical organism was grown from another site (usually blood) in 18 of these 24 patients. The bone marrow culture provided the only positive result in six patients and the first positive result in eight patients. CONCLUSIONS: Utilization of bone marrow cultures for mycobacteria and fungi declined at our institution. Bone marrow and blood cultures were highly concordant. However, the majority of positive bone marrow cultures provided useful information.     

感染性心内膜炎的血培养阳性与阴性临床意义

目的　明确血培养阳性与阴性的感染性心内膜炎 (IE)之间在临床特征和预后方面的异同。方法　对63例IE患者 ,根据血培养结果分成阳性组 (N =15 )和阴性组 (N =48) ,比较临床特征和预后。结果　 41例 ( 65 .1% )经超声心动图检出有赘生物 ,两组病人的赘生物检出率、基础心脏病和感染部位一致 ,从入院到确诊时间无显著差异。两组病人入院前有使用抗生素的比率分别为 3 3 .3 %和 85 .4% (P <0 .0 1)。血培养阳性组白细胞计数较阴性组高 (P <0 .0 1) ,因而更易出现发热和脓肿并发症 (P <0 .0 5 ) ,而血培养阴性组更多出现心瓣膜破裂或穿孔 ,严重心衰 ,更多病人施行了心脏换瓣手术 (P <0 .0 5 ) ,但两组病人预后无统计学差异。结论　由于血培养前抗生素的广泛使用 ,IE血培养阳性率明显下降 ,超声心动图检查有助于血培养阴性IE的早期诊断。血培养阴性IE后果更为严重 ,早期诊断和及时的手术换瓣治疗可以改善预后     

Invasive fungal infections at The Norwegian Radium Hospital 1998-2003

The study evaluates the clinical and microbiological data from patients with documented invasive fungal infections at a comprehensive cancer centre in Norway. Relevant microbiology and pathology databases were screened and medical records were reviewed. 17 yeast infections, including 1 case of cryptococcal meningitis, and no mould infections were found. Diagnostically, in 30% of the positive blood cultures Candida only grew in the Mycosis IC/F bottle. Half of the patients had febrile neutropenia, and 30% had undergone complicated abdominal or pelvic surgery. 12 out of 13 positive blood cultures were Candida albicans. 30% of the patients died of acute septic candidiasis. Within 14 months 90% of the patients were dead from their underlying diseases. A diagnosis of invasive fungal infection is an ominous sign for the patient's overall prognosis.     

Diagnosis and Prevalence of HIV-2 Antibodies in Different Population Subsets in The Netherlands

A serum panel obtained from male homosexuals (n = 278); i.v. drug abusers (n = 99), patients attending a VD clinic (n = 390), blood donors who visited Central or West Africa (n = 573), blood donors who had sexual contact with natives from Central or West Africa (n = 38), blood donors from Surinam, South America (n = 481), individuals positive for anti-HIV-1 (n = 94), individuals with indeterminate HIV-1 western blot (WB) reactions (n = 73), African patients with AIDS or AIDS-related symptoms (n = 30), and random Dutch blood donors (n = 555), was tested with HIV-2 ELISA (ELAVIA-2). Of these 2,611 samples, 32 (1.2%) were repeatedly reactive. Antibodies to gp140/105env were found in 4/32 by HIV-2 WB, and in 1/4 by radioimmunoprecipitation (RIPA). These 4 HIV-2 WB-positive samples were also reactive with gp160/120env in HIV-1 WB, suggesting cross-reactivity. In a spot test with synthetic peptides of the transmembrane glycoprotein of both HIV types, 3/4 were only HIV-1 positive and 1/4 was strongly HIV-2 positive and weakly HIV-1 positive. In inhibition assays with soluble HIV-1 or HIV-2 synthetic peptides in HIV-1 and HIV-2 peptide ELISA, cross-reactivity was excluded, which indicates an HIV variant or HIV-1/HIV-2 double infection. It is concluded that for the moment HIV-2 infection is at low prevalence in risk groups in The Netherlands, and that in addition to WB and RIPA, synthetic peptide assays are useful for differentiation between HIV-1 and HIV-2 antibodies.